I quite think I played this hand without thinking and I went for cheap showdown.I mean his is showing weakness and I never make a try to capitalize the dead money. Especially on the river. I think the K is a great card to represent a bluff. What do you think about a raise on the river?

Well, even if he gives such good odds. I just don't see what we beat on the river.
On the turn of course it's fine to Call while he may even have draws worse PPs/pairs but on the river I'd just fold it.